잠언 17:17 해설: Rashi & Malbim

At all times, love a friend You should always love friends, i.e., to acquire people who love you.

(17-18) A friend loves at all times, etc. A man who gives the hand is void of understanding: Behold the delineation of a friend is that he loves his friend constantly at all times. And at a time of adversity, his love will grow greater until he is like a brother, to sacrifice his life for his friend as if he were his brother. Nevertheless, even though the friend is obligated to do anything for his friend, he is not obligated to enter into surety and give the hand for him. And if he does this because of his love for him, he is one who is void of understanding and does not foresee the outcome.

for he is born a brother for adversity At the time of adversity, the friend will be born to you as a brother, to help you and to participate in your adversity.